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Mallory
Medium

DoS via crafted TLS packet in Snort 3 Detection Engine (Cisco Secure Firewall FTD)

IdentifiersCVE-2026-20006CWE-754

A vulnerability in the TLS cryptography functionality of the Snort 3 Detection Engine in Cisco Secure Firewall Threat Defense (FTD) Software allows an unauthenticated remote attacker to trigger an unexpected restart of the Snort 3 Detection Engine. The issue is attributed to an improper implementation of the TLS protocol; exploitation is performed by sending a crafted TLS packet to an affected system. TLS 1.3 is explicitly noted as not affected.

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Impact

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Successful exploitation can repeatedly restart the Snort 3 Detection Engine, causing the device to drop network traffic and resulting in a denial-of-service (DoS) condition for traffic inspection/forwarding on Cisco Secure FTD deployments.
PUBLIC EXPLOITS

Exploits

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VALID 0 / 0 TOTALView more in app

No public exploit code observed for this vulnerability.

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Threat actor evidence

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Associated malware

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Detection signatures

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Vendor-by-vendor mapping

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